In order to investigate the protective effects of intestinal trefoil factor (ITF) on colonic mucosa in experimental colitis of rats, ITF was detected by RT-PCR and immunohistochemistry at different time points. Three ...In order to investigate the protective effects of intestinal trefoil factor (ITF) on colonic mucosa in experimental colitis of rats, ITF was detected by RT-PCR and immunohistochemistry at different time points. Three days after colitis induction, rats were treated with either 0.9 % saline solution or rhITF. Pathological changes and the expression of iNOS mRNA, NO, MDA and SOD were measured respectively. It was found that ITF was mainly located in goblet cells, significantly higher in model group than in normal group (P<0.05). rhITF could increase the iNOS mRNA expression and NO contents, and there was statistically significant difference between rhITF group and model group (P<0.05). rhITF also caused an increase of MDA and a decrease of SOD, but there was no significant difference between two groups. These results indicated that ITF has apparent therapeutic effects in ulcerative colitis, which may be associated with iNOS and NO.展开更多
The transcription factor nuclear factor κB（NF-κB） plays major roles in inflammatory diseases through regulation of inflammation and cell viability.Multiple sclerosis（MS） is a chronic inflammatory demyelinating a...The transcription factor nuclear factor κB（NF-κB） plays major roles in inflammatory diseases through regulation of inflammation and cell viability.Multiple sclerosis（MS） is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system（CNS）.It has been shown that NF-κB is activated in multiple cell types in the CNS of MS patients,including T cells,microglia/macrophages,astrocytes,oligodendrocytes,and neurons.Interestingly,data from animal model studies,particularly studies of experimental autoimmune encephalomyelitis,have suggested that NF-κB activation in these individual cell types has distinct effects on the development of MS.In this review,we will cover the current literature on NF-κB and the evidence for its role in the development of MS and its animal model experimental autoimmune encephalomyelitis.展开更多
Previous studies have demonstrated that statins improve neurological outcome and promote neuro-vascular recovery after ICH. This study is designed to examine whether simvastatin and atorvastatin affect levels of growt...Previous studies have demonstrated that statins improve neurological outcome and promote neuro-vascular recovery after ICH. This study is designed to examine whether simvastatin and atorvastatin affect levels of growth factors and activate the Akt signaling pathway during the recovery phase after intracerebral hemorrhage (ICH) in rats. Sixty (60) male Wistar rats were subjected to ICH by stereotactic injecttion of 100 μL of autologous blood into the striatum and were treated with or without simvastatin or atorvastatin. Neurological functional outcome was evaluated by behavioral tests (mNSS and corner turn test) at different time points after ICH. Brain extracts were utilized for Enzyme-linked immunosorbent assay (ELISA) analyses to measure vascular endothelial growth factor (VEGF);brain-derived neurotrophin factor (BDNF) expression, and nerve growth factor (NGF). Western blot was used to measure the changes in the Akt-mediated signaling pathway. Both the simvastatin and atorvastatin-treated animals had significant neurological improvement at 2 weeks post-ICH. Simvastatin and atorvastatin treatment increased the expression of BDNF, VEGF and NGF in both low- and high-dose groups at 7 days after ICH (p < 0.05). Phosphorylation of Akt, glycogen synthase kinase-3β (GSK-3β), and cAMP response element-binding proteins (CREB) were also increased at 7 days after statin treatment. These results suggest that the therapeutic effects of statins after experimental ICH may be mediated by the transient induction of BDNF, VEGF and NGF expression and the activation of the Akt-mediated signaling pathway.展开更多
Tumor necrosis factor-α (TNF-α) plays a key role in the pathogenesis of experimental autoimmune neuritis (EAN) as well as Guillain-Barre syndrome. The proposed pathogenesis of TNF-α associated neuropathies involves...Tumor necrosis factor-α (TNF-α) plays a key role in the pathogenesis of experimental autoimmune neuritis (EAN) as well as Guillain-Barre syndrome. The proposed pathogenesis of TNF-α associated neuropathies involves immune-mediated attack to blood-nerve barrier, aggravated production of pro-inflammatory cytokines, and the induction of Schwann cells apoptosis. TNF-α may play a regulatory role by increasing production of interleukin-1 in macrophages, attenuating T cell receptor signaling and regulating apoptosis of potentially autoreactive T cells in EAN. The data suggest that antagonizing TNF-α functions or suppressing TNF-α production may be useful in the acute phase of EAN treatment, but further studies are required.展开更多
Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch an...Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch and rib height of 4.5 and 1.0 mm.respectively.Experimental results show that the heat transfer and thermal performance of Therminol-55 liquid phase heat transfer fluid in the ribbed tube are considerably improved compared to those of the smooth tube.The Nusselt number increase with the increase of Reynolds number.The increase in heat transfer rate of the ribbed tube has a mean value of 2.24 times.Also,the pressure drop results reveal that the average friction factor of the ribbed tube is in a range of 2.4 and 2.8 times over the smooth tube.Numerical simulations of three-dimensional flow behavior of Therminol-55 liquid phase heat transfer fluid are carried out using three different turbulence models in the ribbed tube.The numerical results show that the heat transfer of ribbed tube is improved because vortices are generated behind ribs,which produce some disruptions to fluid flow and enhance heat transfer compared with smooth tube.The numerical results prove that the ribbed tube can improve heat transfer and fluid flow performances of Therminol liquid phase heat transfer fluid.展开更多
· AIM: To investigate the expression of complement factors in the posterior scleral fibroblasts of guinea pigs with negative lens-defocused myopia.· METHODS: Eighteen guinea pigs were assigned randomly to tw...· AIM: To investigate the expression of complement factors in the posterior scleral fibroblasts of guinea pigs with negative lens-defocused myopia.· METHODS: Eighteen guinea pigs were assigned randomly to two groups: the negative lens-defocused group(NLD group, n =9) and the normal control without treatment group(NC group, n =9). The effect of myopic induction was compared in three subgroups: eyes treated with a-10.00 D negative lens in the NLD group(NL group), eyes treated with a plano(0 D) lens in the NLD group(PL group), and untreated right eyes in the NC group(NC group). The following analyses were conducted at four weeks: examination of the refractive error via retinoscopy, assessment of complement C5b-9expression in the posterior scleral fibroblasts using immunohistochemistry, and measurements of complement C1 q and C3 protein levels in the posterior sclera by Western blot.·RESULTS: After an induction period of four weeks, a significant myopic shift was detected in the eyes of the NL group, relative to that of the PL and NC groups(P 【0.05). Data analysis showed a significant increase in the percentage of C5b-9 immunopositive fibroblasts in the posterior sclera of the NL group eyes, compared to the PL group(q =11.50, P 【0.001). Significantly higher levels of C1q(q =4.94, P =0.01) and C3(q =4.07, P =0.03)protein were detected in the posterior sclera of NL group eyes, compared to the PL group. There were no significant difference between the PL and NC groups for C5b-9(q =2.44, P =0.10), C1q(q =1.55, P =0.53) and C3(q =0.98, P =0.77) in the posterior sclera.·CONCLUSION: The data from present study provide evidence of the up-regulation of C5b-9, C1 q and C3 in the posterior scleral fibroblasts in a NLD myopic animal model. The results suggest that the complement system may be involved in the development of myopia.展开更多
Effects of some methodological factors on in vitro measures of gas production（GP, mL/g DM）, CH4production（mL/g DM） and proportion（% CH4 on total GP） were investigated by meta-analysis. These factors were conside...Effects of some methodological factors on in vitro measures of gas production（GP, mL/g DM）, CH4production（mL/g DM） and proportion（% CH4 on total GP） were investigated by meta-analysis. These factors were considered：pressure in the GP equipment（0 = constant; 1 = increasing）, incubation time（0 = 24; 1 = ≥ 48 h）, time of rumen fluid collection（0 = before feeding; 1 = after feeding of donor animals）, donor species of rumen fluid（0 = sheep; 1 =bovine）, presence of N in the buffer solution（0 = presence; 1 = absence）, and ratio between amount of buffered rumen fluid and feed sample（BRF/FS; 0 = ≤ 130 mL/g DM; 1 = 130–140 mL/g DM; 2 = ≥ 140 mL/g DM）. The NDF content of feed sample incubated（NDF） was considered as a continuous variable. From an initial database of 105 papers, 58 were discarded because one of the above-mentioned factors was not stated. After discarding 17 papers,the final dataset comprised 30 papers（339 observations）. A preliminary mixed model analysis was carried out on experimental data considering the study as random factor. Variables adjusted for study effect were analyzed using a backward stepwise analysis including the above-mentioned variables. The analysis showed that the extension of incubation time and reduction of NDF increased GP and CH4 values. Values of GP and CH4 also increased when rumen fluid was collected after feeding compared to before feeding（＋26.4 and ＋9.0 mL/g DM, for GP and CH4）,from bovine compared to sheep（＋32.8 and ＋5.2 mL/g DM, for GP and CH4）, and when the buffer solution did not contain N（＋24.7 and ＋6.7 mL/g DM for GP and CH4）. The increase of BRF/FS ratio enhanced GP and CH4production（＋7.7 and ＋3.3 mL/g DM per each class of increase, respectively）. In vitro techniques for measuring GP and CH4 production are mostly used as screening methods, thus a full standardization of such techniques is not feasible. However, a greater harmonization of analytical procedures（i.e., a reduction in the number of available protocols） would be useful to facilitate comparison between results of different experiments.展开更多
In this paper, the crack initiation characteristics of compression-shear plane crack with hydraulic pressure were studied by using theoretical analysis and experimental verification methods. The formula derivation pro...In this paper, the crack initiation characteristics of compression-shear plane crack with hydraulic pressure were studied by using theoretical analysis and experimental verification methods. The formula derivation process of stress intensity factor of crack tip and open-type crack initiation angle and initiation strength was expounded in detail. Cement mortar specimens prefabricated with open-type crack were made for biaxial compression test. The results show that the mode I stress intensity factor is inversely proportional to the dip angle of pre-exciting crack, water pressure and crack width. The fracture toughness is most easily achieved when the dip angle of pre-exciting crack is 60°. The mode II stress intensity factor is symmetrically distributed with the dip angle and independent of the water pressure and crack width. For open-type crack, the crack initiation angle decreases with the increase of the dip angle of pre-exciting crack, water pressure and crack width;the crack initiation strength is inversely proportional to the water pressure and proportional to the lateral pressure. The research results can provide ideas for the study of crack initiation under the coupling of ground stress and osmotic pressure in tunnel engineering.展开更多
OBJECTIVE: To determine the therapeutic effect and potential mechanism of Huatan Tongluo decoction on rats with collagen-induced arthritis.METHODS: Forty specific pathogen-free Wistar rats were selected, and 10 were r...OBJECTIVE: To determine the therapeutic effect and potential mechanism of Huatan Tongluo decoction on rats with collagen-induced arthritis.METHODS: Forty specific pathogen-free Wistar rats were selected, and 10 were randomly selected as the control(group 1). The remaining rats were injected intradermally with emulsified type Ⅱ bovine collagen at the tail base and back, followed by a booster 7 d post first immunization. After establishing collagen-induced arthritis(CIA), rats were randomly divided into three groups(n = 10). The rats were treated orally for 30 d as follows: group 1, saline; group 2, model(saline); group 3, tripterygium polyglycoside(TP; 7.81 mg/kg, positive control);group 4, Huatan Tongluo decoction(HTTL; 7.5 g/kg). Body weight, ankle swelling and arthritis index were measured over the course of the study. The rats were sacrificed 30 d after treatment. Morphological changes in the synovium were observed by hematoxylin and eosin staining. Pannus formation and synovial thickness in the left ankle were observed by color Doppler ultrasoundVascular endothelial growth factor(VEGF) and VEGFR2 protein levels were measured by immunohistochemistry.VEGF/VEGFR2 mRNA levels were measured by real-time quantitative polymerase chain reaction.RESULTS: Compared with the model group, a significantly lower arthritis index was observed in the positive control group(P < 0.05) and HTTL group(P < 0.01), after treatment. Both positive control and HTTL reduced intra-articular pannus formation and synovial thickening. Furthermore, VEGF mRNA,and VEGFR2 protein and mRNA levels were significantly downregulated(P < 0.05) in the treatment groups.CONCLUSION: Inhibition of the expression of VEGF and VEGFR2 in synovial tissues and the formation of pannus and synovial hyperplasia may be part of the mechanism of HTTL for relieving the symptoms of rheumatoid arthritis in CIA rats.展开更多
The effect of triptolide （TP） on the expression of receptor activator of nuclear factor-κB ligand （RANKL） and osteoprotegerin （OPG） was explored in rat adjuvant induced arthritis （AA）. AA was induced in Wista...The effect of triptolide （TP） on the expression of receptor activator of nuclear factor-κB ligand （RANKL） and osteoprotegerin （OPG） was explored in rat adjuvant induced arthritis （AA）. AA was induced in Wistar rats. Arthritis rats were treated with TP and methotrexate （MTX） at the onset （day 9） of arthritis. On the peak of arthritis （day 24）, the expression of RANKL and OPG protein in the joints and RANKL mRNA in peripheral blood mononuclear cells （PBMC） was detected. TNF-α and IL-1β levels in peripheral blood were determined. Bone erosion scores were also evaluated. The results showed that bone erosion scores in TP and MTX groups were lower than in AA group （.P〈0.01） ; The expression levels of RANKL in the synovium （P〈0.01） and bone （P〈0.05）, and OPG level in synovium （P〈0.05） were lower in TP group than in AA group （P〈0.05）. In TP group, the expression levels of RANKL mRNA and TNF-α, IL-1β in PBMC were lower than in AA group （all P〈0.01）. It was concluded that TP could inhibit rat adjuvant arthritis bone erosion by suppressing the expression of RANKL.展开更多
Objective: The use of animal models of aortic stenosis(AS) remains essential to further elucidate its pathophysiology and to evaluate new therapeutic strategies. The waved-2 mouse AS model has been proposed;data have ...Objective: The use of animal models of aortic stenosis(AS) remains essential to further elucidate its pathophysiology and to evaluate new therapeutic strategies. The waved-2 mouse AS model has been proposed;data have indicated that while aortic regurgitation(AR) is effectively induced, development of AS is rare.We aimed to evaluate the effect of high-fat diet(HFD) and vitamin D_3 supplementation in this model.Methods: HFD and subcutaneous vitamin D_3 injections were initiated at the age of 6 weeks until the age of 6(n = 16, 6-month treatment group) and 9(n = 11, 9-month treatment group) months. Twelve waved-2 mice without supplementation were used as control. Echocardiography was performed at 3, 6 and 9 months. Blood serum analysis(calcium, 1,25(OH)_2D_3 and cholesterol), histology and immunohistochemistry(CD-31, CD-68 and osteopontin) were evaluated at the end of the experiment(6 or 9 months).Results: Total cholesterol and 1,25(OH)_2D_3 were significantly increased relative to the control group. HFD and vitamin D_3 supplementation did result in improvements to the model, since AS was only detected in 6(15.3%) mice(2 in the 3 groups) and AR was developed in the remaining animals. Echocardiographic parameters, fibrosis, thickness, inflammation and valvular calcification, were not significantly different between the 6-month treatment and control groups. Similar results were also observed in the 9-month treatment group.Conclusion: These results suggest that HFD and vitamin D_3 supplementation have no effect in the waved-2 mouse model. This model essentially mimics AR and rarely AS. Further studies are needed to find a reliable animal model of AS.展开更多
Myelin-associated inhibitory factors within the central nervous system（CNS） are considered to be one of the main obstacles for axonal regeneration following disease or injury. The nogo receptor 1（NgR1） has been we...Myelin-associated inhibitory factors within the central nervous system（CNS） are considered to be one of the main obstacles for axonal regeneration following disease or injury. The nogo receptor 1（NgR1） has been well documented to play a key role in limiting axonal regrowth in the injured and diseased mammalian CNS. However, the role of nogo receptor in immune cell activation during CNS inflammation is yet to be mechanistically elucidated. Microglia/macrophages are immune cells that are regarded as pathogenic contributors to inflammatory demyelinating lesions in multiple sclerosis（MS）. In this study, the animal model of MS, experimental autoimmune encephalomyelitis（EAE） was induced in ngr1^＋/＋ and ngr1^–/– female mice following injection with the myelin oligodendrocyte glycoprotein（MOG_（35–55）） peptide. A fatemap analysis of microglia/macrophages was performed throughout spinal cord sections of EAE-induced mice at clinical scores of 0, 1, 2 and 3, respectively（increasing locomotor disability） from both genotypes, using the CD11 b and Iba1 cell markers. Western immunoblotting using lysates from isolated spinal cord microglia/macrophages, along with immunohistochemistry and flow cytometric analysis, was performed to demonstrate the expression of nogo receptor and its two homologs during EAE progression. Myelin protein engulfment during EAE progression in ngr1^＋/＋ and ngr1^–/– mice was demonstrated by western immunblotting of lysates from isolated spinal cord microglia/macrophages, detecting levels of Nogo-A and MOG. The numbers of M1 and M2 microglia/macrophage phenotypes present in the spinal cords of EAE-induced ngr1^＋/＋ and ngr1^–/– mice, were assessed by flow cytometric analysis using CD38 and Erg-2 markers. A significant difference in microglia/macrophage numbers between ngr1^＋/＋ and ngr1^–/– mice was identified during the progression of the clinical symptoms of EAE, in the white versus gray matter regions of the spinal cord. This difference was unrelated to the expression of Ng R on these macrophage/microglial cells. We have identified that as EAE progresses, the phagocytic activity of microglia/macrophages with myelin debris, in ngr1^–/– mice, was enhanced. Moreover, we show a modulation from a predominant M1-pathogenic to the M2-neurotrophic cell phenotype in the ngr1^–/– mice during EAE progression. These findings suggest that CNS-specific macrophages and microglia of ngr1^–/– mice may exhibit an enhanced capacity to clear inhibitory molecules that are sequestered in inflammatory lesions.展开更多
AIM: To evaluate the influence of an intravitreal injection of bevacizumab and fasudil on the retinal vascular endothelial growth factor(VEGF),tumor necrosis factor alpha(TNFα),and caspase 3 levels in a diabetic rabb...AIM: To evaluate the influence of an intravitreal injection of bevacizumab and fasudil on the retinal vascular endothelial growth factor(VEGF),tumor necrosis factor alpha(TNFα),and caspase 3 levels in a diabetic rabbit model. · METHODS: The study included 6 healthy rabbits(Group 1),6 rabbits with experimentally induced diabetes mellitus(DM)(Group 2),7 rabbits with experimentally induced DM to which intravitreal bevacizumab was administered(Group 3),and 7 rabbits with experimentally induced DM to which intravitreal fasudil was administered(Group 4). An intravitreal injection of 1.25mg/50μL bevacizumab in the right eye of rabbits in Group 3 and an intravitreal injection of 0.0064mg/50μL fasudil in the right eye of rabbits in Group 4 were administered on day 21 after the induction of DM. The studied eyes of the rabbits were enucleated three days after the intravitreal injection. The TNFα,VEGF,and caspase 3 levels were determined using the ELISA method. · RESULTS: There was a statistically significant difference in the VEGF and caspase 3 levels between groups(P =0.005 and P =0.013,respectively),but the TNF α level did not differ significantly between groups(P = 0.792). It was found that VEGF levels were significantly lower in Group 1 and Group 3 than in Group 2 using the Mann-Whitney U test with the Bonferroni correction(P = 0.004 for both comparison). There was no statistically significant difference between other groups with regard to VEGF levels(the P value ranged between 0.015 and 0.886). Although the P values of the caspase 3 levels were 0.015 for Group 1 and Group 4,0.038 for Group 2and Group 3,and 0.018 for Group 3 and Group 4,these P values remained above the threshold P value of 0.0083,which was the statistically significant level for post hoc tests. ·CONCLUSION: An intravitreal injection of bevacizumab decreased both the VEGF level,which plays a role in angiogenesis,and the caspase 3 level,which plays a role in apoptosis. Although not as effective as bevacizumab,fasudil had a beneficial effect on the VEGF levels but significantly increased the caspase 3 levels.展开更多
This paper introduces the origin and progress of Tropical and South Subtropical Agricultural Comprehensive Experimental Station( hereinafter referred to as experimental station) CATAS( Jiangmen),formulates the thought...This paper introduces the origin and progress of Tropical and South Subtropical Agricultural Comprehensive Experimental Station( hereinafter referred to as experimental station) CATAS( Jiangmen),formulates the thought for construction of experimental station,analyzes the restrictive factors and puts forward corresponding countermeasures in order to provide reference for the decision- making and implementation of constructing the experimental station.展开更多
文摘In order to investigate the protective effects of intestinal trefoil factor (ITF) on colonic mucosa in experimental colitis of rats, ITF was detected by RT-PCR and immunohistochemistry at different time points. Three days after colitis induction, rats were treated with either 0.9 % saline solution or rhITF. Pathological changes and the expression of iNOS mRNA, NO, MDA and SOD were measured respectively. It was found that ITF was mainly located in goblet cells, significantly higher in model group than in normal group (P<0.05). rhITF could increase the iNOS mRNA expression and NO contents, and there was statistically significant difference between rhITF group and model group (P<0.05). rhITF also caused an increase of MDA and a decrease of SOD, but there was no significant difference between two groups. These results indicated that ITF has apparent therapeutic effects in ulcerative colitis, which may be associated with iNOS and NO.
基金supported by grants from the National Institutes of Health(NS094151 and NS105689)the National Multiple Sclerosis Society(RG5239-A-3)(to WL)
文摘The transcription factor nuclear factor κB（NF-κB） plays major roles in inflammatory diseases through regulation of inflammation and cell viability.Multiple sclerosis（MS） is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system（CNS）.It has been shown that NF-κB is activated in multiple cell types in the CNS of MS patients,including T cells,microglia/macrophages,astrocytes,oligodendrocytes,and neurons.Interestingly,data from animal model studies,particularly studies of experimental autoimmune encephalomyelitis,have suggested that NF-κB activation in these individual cell types has distinct effects on the development of MS.In this review,we will cover the current literature on NF-κB and the evidence for its role in the development of MS and its animal model experimental autoimmune encephalomyelitis.
文摘Previous studies have demonstrated that statins improve neurological outcome and promote neuro-vascular recovery after ICH. This study is designed to examine whether simvastatin and atorvastatin affect levels of growth factors and activate the Akt signaling pathway during the recovery phase after intracerebral hemorrhage (ICH) in rats. Sixty (60) male Wistar rats were subjected to ICH by stereotactic injecttion of 100 μL of autologous blood into the striatum and were treated with or without simvastatin or atorvastatin. Neurological functional outcome was evaluated by behavioral tests (mNSS and corner turn test) at different time points after ICH. Brain extracts were utilized for Enzyme-linked immunosorbent assay (ELISA) analyses to measure vascular endothelial growth factor (VEGF);brain-derived neurotrophin factor (BDNF) expression, and nerve growth factor (NGF). Western blot was used to measure the changes in the Akt-mediated signaling pathway. Both the simvastatin and atorvastatin-treated animals had significant neurological improvement at 2 weeks post-ICH. Simvastatin and atorvastatin treatment increased the expression of BDNF, VEGF and NGF in both low- and high-dose groups at 7 days after ICH (p < 0.05). Phosphorylation of Akt, glycogen synthase kinase-3β (GSK-3β), and cAMP response element-binding proteins (CREB) were also increased at 7 days after statin treatment. These results suggest that the therapeutic effects of statins after experimental ICH may be mediated by the transient induction of BDNF, VEGF and NGF expression and the activation of the Akt-mediated signaling pathway.
文摘Tumor necrosis factor-α (TNF-α) plays a key role in the pathogenesis of experimental autoimmune neuritis (EAN) as well as Guillain-Barre syndrome. The proposed pathogenesis of TNF-α associated neuropathies involves immune-mediated attack to blood-nerve barrier, aggravated production of pro-inflammatory cytokines, and the induction of Schwann cells apoptosis. TNF-α may play a regulatory role by increasing production of interleukin-1 in macrophages, attenuating T cell receptor signaling and regulating apoptosis of potentially autoreactive T cells in EAN. The data suggest that antagonizing TNF-α functions or suppressing TNF-α production may be useful in the acute phase of EAN treatment, but further studies are required.
基金Supported by the National Natural Science Foundation of China(11472093 and21276056)
文摘Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch and rib height of 4.5 and 1.0 mm.respectively.Experimental results show that the heat transfer and thermal performance of Therminol-55 liquid phase heat transfer fluid in the ribbed tube are considerably improved compared to those of the smooth tube.The Nusselt number increase with the increase of Reynolds number.The increase in heat transfer rate of the ribbed tube has a mean value of 2.24 times.Also,the pressure drop results reveal that the average friction factor of the ribbed tube is in a range of 2.4 and 2.8 times over the smooth tube.Numerical simulations of three-dimensional flow behavior of Therminol-55 liquid phase heat transfer fluid are carried out using three different turbulence models in the ribbed tube.The numerical results show that the heat transfer of ribbed tube is improved because vortices are generated behind ribs,which produce some disruptions to fluid flow and enhance heat transfer compared with smooth tube.The numerical results prove that the ribbed tube can improve heat transfer and fluid flow performances of Therminol liquid phase heat transfer fluid.
基金Supported by the National Natural Science Foundation of China(No.81070755)
文摘· AIM: To investigate the expression of complement factors in the posterior scleral fibroblasts of guinea pigs with negative lens-defocused myopia.· METHODS: Eighteen guinea pigs were assigned randomly to two groups: the negative lens-defocused group(NLD group, n =9) and the normal control without treatment group(NC group, n =9). The effect of myopic induction was compared in three subgroups: eyes treated with a-10.00 D negative lens in the NLD group(NL group), eyes treated with a plano(0 D) lens in the NLD group(PL group), and untreated right eyes in the NC group(NC group). The following analyses were conducted at four weeks: examination of the refractive error via retinoscopy, assessment of complement C5b-9expression in the posterior scleral fibroblasts using immunohistochemistry, and measurements of complement C1 q and C3 protein levels in the posterior sclera by Western blot.·RESULTS: After an induction period of four weeks, a significant myopic shift was detected in the eyes of the NL group, relative to that of the PL and NC groups(P 【0.05). Data analysis showed a significant increase in the percentage of C5b-9 immunopositive fibroblasts in the posterior sclera of the NL group eyes, compared to the PL group(q =11.50, P 【0.001). Significantly higher levels of C1q(q =4.94, P =0.01) and C3(q =4.07, P =0.03)protein were detected in the posterior sclera of NL group eyes, compared to the PL group. There were no significant difference between the PL and NC groups for C5b-9(q =2.44, P =0.10), C1q(q =1.55, P =0.53) and C3(q =0.98, P =0.77) in the posterior sclera.·CONCLUSION: The data from present study provide evidence of the up-regulation of C5b-9, C1 q and C3 in the posterior scleral fibroblasts in a NLD myopic animal model. The results suggest that the complement system may be involved in the development of myopia.
基金financed by the project “ARCHAEA- Feeding strategies to reduce methane emissions from dairy cows,”Veneto Region Rural Development Programme (RDP) 2007–2013 “Progetto di Ateneo cod. CPDA 155250”, University of Padova, Italy
文摘Effects of some methodological factors on in vitro measures of gas production（GP, mL/g DM）, CH4production（mL/g DM） and proportion（% CH4 on total GP） were investigated by meta-analysis. These factors were considered：pressure in the GP equipment（0 = constant; 1 = increasing）, incubation time（0 = 24; 1 = ≥ 48 h）, time of rumen fluid collection（0 = before feeding; 1 = after feeding of donor animals）, donor species of rumen fluid（0 = sheep; 1 =bovine）, presence of N in the buffer solution（0 = presence; 1 = absence）, and ratio between amount of buffered rumen fluid and feed sample（BRF/FS; 0 = ≤ 130 mL/g DM; 1 = 130–140 mL/g DM; 2 = ≥ 140 mL/g DM）. The NDF content of feed sample incubated（NDF） was considered as a continuous variable. From an initial database of 105 papers, 58 were discarded because one of the above-mentioned factors was not stated. After discarding 17 papers,the final dataset comprised 30 papers（339 observations）. A preliminary mixed model analysis was carried out on experimental data considering the study as random factor. Variables adjusted for study effect were analyzed using a backward stepwise analysis including the above-mentioned variables. The analysis showed that the extension of incubation time and reduction of NDF increased GP and CH4 values. Values of GP and CH4 also increased when rumen fluid was collected after feeding compared to before feeding（＋26.4 and ＋9.0 mL/g DM, for GP and CH4）,from bovine compared to sheep（＋32.8 and ＋5.2 mL/g DM, for GP and CH4）, and when the buffer solution did not contain N（＋24.7 and ＋6.7 mL/g DM for GP and CH4）. The increase of BRF/FS ratio enhanced GP and CH4production（＋7.7 and ＋3.3 mL/g DM per each class of increase, respectively）. In vitro techniques for measuring GP and CH4 production are mostly used as screening methods, thus a full standardization of such techniques is not feasible. However, a greater harmonization of analytical procedures（i.e., a reduction in the number of available protocols） would be useful to facilitate comparison between results of different experiments.
文摘In this paper, the crack initiation characteristics of compression-shear plane crack with hydraulic pressure were studied by using theoretical analysis and experimental verification methods. The formula derivation process of stress intensity factor of crack tip and open-type crack initiation angle and initiation strength was expounded in detail. Cement mortar specimens prefabricated with open-type crack were made for biaxial compression test. The results show that the mode I stress intensity factor is inversely proportional to the dip angle of pre-exciting crack, water pressure and crack width. The fracture toughness is most easily achieved when the dip angle of pre-exciting crack is 60°. The mode II stress intensity factor is symmetrically distributed with the dip angle and independent of the water pressure and crack width. For open-type crack, the crack initiation angle decreases with the increase of the dip angle of pre-exciting crack, water pressure and crack width;the crack initiation strength is inversely proportional to the water pressure and proportional to the lateral pressure. The research results can provide ideas for the study of crack initiation under the coupling of ground stress and osmotic pressure in tunnel engineering.
基金Supported by National Natural Science Foundation of China Funded project:Study on the Relation between Rheumatic Arthralgia Induced by Phlem and Blood Stasis and Joints Angiogenesis of Rheumatoid Arthritis(No.81473574)Internal Project of Xiamen Hospital of Traditional Chinese Medicine Funded Project:Investigating the Therapeutic Effect and Mechanism of Resolving Phlegm and Turbidity Decoction(No.2015003)Nature Science Foundation of Fujian Province Funded Project:Studies on siRNA Drugs by Down-Regulation of both c-FLIPL and MADD for Targeted Ovarian Cancer Therapy(No.2015J01347)
文摘OBJECTIVE: To determine the therapeutic effect and potential mechanism of Huatan Tongluo decoction on rats with collagen-induced arthritis.METHODS: Forty specific pathogen-free Wistar rats were selected, and 10 were randomly selected as the control(group 1). The remaining rats were injected intradermally with emulsified type Ⅱ bovine collagen at the tail base and back, followed by a booster 7 d post first immunization. After establishing collagen-induced arthritis(CIA), rats were randomly divided into three groups(n = 10). The rats were treated orally for 30 d as follows: group 1, saline; group 2, model(saline); group 3, tripterygium polyglycoside(TP; 7.81 mg/kg, positive control);group 4, Huatan Tongluo decoction(HTTL; 7.5 g/kg). Body weight, ankle swelling and arthritis index were measured over the course of the study. The rats were sacrificed 30 d after treatment. Morphological changes in the synovium were observed by hematoxylin and eosin staining. Pannus formation and synovial thickness in the left ankle were observed by color Doppler ultrasoundVascular endothelial growth factor(VEGF) and VEGFR2 protein levels were measured by immunohistochemistry.VEGF/VEGFR2 mRNA levels were measured by real-time quantitative polymerase chain reaction.RESULTS: Compared with the model group, a significantly lower arthritis index was observed in the positive control group(P < 0.05) and HTTL group(P < 0.01), after treatment. Both positive control and HTTL reduced intra-articular pannus formation and synovial thickening. Furthermore, VEGF mRNA,and VEGFR2 protein and mRNA levels were significantly downregulated(P < 0.05) in the treatment groups.CONCLUSION: Inhibition of the expression of VEGF and VEGFR2 in synovial tissues and the formation of pannus and synovial hyperplasia may be part of the mechanism of HTTL for relieving the symptoms of rheumatoid arthritis in CIA rats.
文摘The effect of triptolide （TP） on the expression of receptor activator of nuclear factor-κB ligand （RANKL） and osteoprotegerin （OPG） was explored in rat adjuvant induced arthritis （AA）. AA was induced in Wistar rats. Arthritis rats were treated with TP and methotrexate （MTX） at the onset （day 9） of arthritis. On the peak of arthritis （day 24）, the expression of RANKL and OPG protein in the joints and RANKL mRNA in peripheral blood mononuclear cells （PBMC） was detected. TNF-α and IL-1β levels in peripheral blood were determined. Bone erosion scores were also evaluated. The results showed that bone erosion scores in TP and MTX groups were lower than in AA group （.P〈0.01） ; The expression levels of RANKL in the synovium （P〈0.01） and bone （P〈0.05）, and OPG level in synovium （P〈0.05） were lower in TP group than in AA group （P〈0.05）. In TP group, the expression levels of RANKL mRNA and TNF-α, IL-1β in PBMC were lower than in AA group （all P〈0.01）. It was concluded that TP could inhibit rat adjuvant arthritis bone erosion by suppressing the expression of RANKL.
基金supported by the French Government,managed by the National Research Agency(ANR)under the program‘‘Investissements d’avenir" with the reference ANR-16-RHUS-0003(RHU project ‘‘Search Treatment and Improve Outcome of Patients with Aortic Stenosis"(STOP-AS)-Hélène Eltchaninoff)Bérénice Colleville’s doctoral program was funded by the Fédération Hospitalo-Universitaire ‘‘Early markers of cardiovascular REMODeling in Valvulopathy and Heart Failure"(REMOD-VHF)and the Rouen Normandy University
文摘Objective: The use of animal models of aortic stenosis(AS) remains essential to further elucidate its pathophysiology and to evaluate new therapeutic strategies. The waved-2 mouse AS model has been proposed;data have indicated that while aortic regurgitation(AR) is effectively induced, development of AS is rare.We aimed to evaluate the effect of high-fat diet(HFD) and vitamin D_3 supplementation in this model.Methods: HFD and subcutaneous vitamin D_3 injections were initiated at the age of 6 weeks until the age of 6(n = 16, 6-month treatment group) and 9(n = 11, 9-month treatment group) months. Twelve waved-2 mice without supplementation were used as control. Echocardiography was performed at 3, 6 and 9 months. Blood serum analysis(calcium, 1,25(OH)_2D_3 and cholesterol), histology and immunohistochemistry(CD-31, CD-68 and osteopontin) were evaluated at the end of the experiment(6 or 9 months).Results: Total cholesterol and 1,25(OH)_2D_3 were significantly increased relative to the control group. HFD and vitamin D_3 supplementation did result in improvements to the model, since AS was only detected in 6(15.3%) mice(2 in the 3 groups) and AR was developed in the remaining animals. Echocardiographic parameters, fibrosis, thickness, inflammation and valvular calcification, were not significantly different between the 6-month treatment and control groups. Similar results were also observed in the 9-month treatment group.Conclusion: These results suggest that HFD and vitamin D_3 supplementation have no effect in the waved-2 mouse model. This model essentially mimics AR and rarely AS. Further studies are needed to find a reliable animal model of AS.
基金supported by Multiple Sclerosis Research Australia and Trish Multiple Sclerosis Research Foundation Postgraduate Scholarship(to JYL)the National Multiple Sclerosis Society Project Grant#RG4398A1/1+2 种基金International Progressive Multiple Sclerosis Alliance Challenge Award#PA0065Multiple Sclerosis Research Australia and Trish Multiple Sclerosis Research Foundation#15-022Bethlehem Griffiths Research Foundation#BGRF1706(to SP)
文摘Myelin-associated inhibitory factors within the central nervous system（CNS） are considered to be one of the main obstacles for axonal regeneration following disease or injury. The nogo receptor 1（NgR1） has been well documented to play a key role in limiting axonal regrowth in the injured and diseased mammalian CNS. However, the role of nogo receptor in immune cell activation during CNS inflammation is yet to be mechanistically elucidated. Microglia/macrophages are immune cells that are regarded as pathogenic contributors to inflammatory demyelinating lesions in multiple sclerosis（MS）. In this study, the animal model of MS, experimental autoimmune encephalomyelitis（EAE） was induced in ngr1^＋/＋ and ngr1^–/– female mice following injection with the myelin oligodendrocyte glycoprotein（MOG_（35–55）） peptide. A fatemap analysis of microglia/macrophages was performed throughout spinal cord sections of EAE-induced mice at clinical scores of 0, 1, 2 and 3, respectively（increasing locomotor disability） from both genotypes, using the CD11 b and Iba1 cell markers. Western immunoblotting using lysates from isolated spinal cord microglia/macrophages, along with immunohistochemistry and flow cytometric analysis, was performed to demonstrate the expression of nogo receptor and its two homologs during EAE progression. Myelin protein engulfment during EAE progression in ngr1^＋/＋ and ngr1^–/– mice was demonstrated by western immunblotting of lysates from isolated spinal cord microglia/macrophages, detecting levels of Nogo-A and MOG. The numbers of M1 and M2 microglia/macrophage phenotypes present in the spinal cords of EAE-induced ngr1^＋/＋ and ngr1^–/– mice, were assessed by flow cytometric analysis using CD38 and Erg-2 markers. A significant difference in microglia/macrophage numbers between ngr1^＋/＋ and ngr1^–/– mice was identified during the progression of the clinical symptoms of EAE, in the white versus gray matter regions of the spinal cord. This difference was unrelated to the expression of Ng R on these macrophage/microglial cells. We have identified that as EAE progresses, the phagocytic activity of microglia/macrophages with myelin debris, in ngr1^–/– mice, was enhanced. Moreover, we show a modulation from a predominant M1-pathogenic to the M2-neurotrophic cell phenotype in the ngr1^–/– mice during EAE progression. These findings suggest that CNS-specific macrophages and microglia of ngr1^–/– mice may exhibit an enhanced capacity to clear inhibitory molecules that are sequestered in inflammatory lesions.
基金Supported by the Scientific Research Project Coordination Unit of Abant Izzet Baysal University
文摘AIM: To evaluate the influence of an intravitreal injection of bevacizumab and fasudil on the retinal vascular endothelial growth factor(VEGF),tumor necrosis factor alpha(TNFα),and caspase 3 levels in a diabetic rabbit model. · METHODS: The study included 6 healthy rabbits(Group 1),6 rabbits with experimentally induced diabetes mellitus(DM)(Group 2),7 rabbits with experimentally induced DM to which intravitreal bevacizumab was administered(Group 3),and 7 rabbits with experimentally induced DM to which intravitreal fasudil was administered(Group 4). An intravitreal injection of 1.25mg/50μL bevacizumab in the right eye of rabbits in Group 3 and an intravitreal injection of 0.0064mg/50μL fasudil in the right eye of rabbits in Group 4 were administered on day 21 after the induction of DM. The studied eyes of the rabbits were enucleated three days after the intravitreal injection. The TNFα,VEGF,and caspase 3 levels were determined using the ELISA method. · RESULTS: There was a statistically significant difference in the VEGF and caspase 3 levels between groups(P =0.005 and P =0.013,respectively),but the TNF α level did not differ significantly between groups(P = 0.792). It was found that VEGF levels were significantly lower in Group 1 and Group 3 than in Group 2 using the Mann-Whitney U test with the Bonferroni correction(P = 0.004 for both comparison). There was no statistically significant difference between other groups with regard to VEGF levels(the P value ranged between 0.015 and 0.886). Although the P values of the caspase 3 levels were 0.015 for Group 1 and Group 4,0.038 for Group 2and Group 3,and 0.018 for Group 3 and Group 4,these P values remained above the threshold P value of 0.0083,which was the statistically significant level for post hoc tests. ·CONCLUSION: An intravitreal injection of bevacizumab decreased both the VEGF level,which plays a role in angiogenesis,and the caspase 3 level,which plays a role in apoptosis. Although not as effective as bevacizumab,fasudil had a beneficial effect on the VEGF levels but significantly increased the caspase 3 levels.
文摘This paper introduces the origin and progress of Tropical and South Subtropical Agricultural Comprehensive Experimental Station( hereinafter referred to as experimental station) CATAS( Jiangmen),formulates the thought for construction of experimental station,analyzes the restrictive factors and puts forward corresponding countermeasures in order to provide reference for the decision- making and implementation of constructing the experimental station.
